Editing Vertical bar (section)

===Physics===
The vertical bar is used in [[bra–ket notation]] in [[quantum physics]]. Examples:
* <math>|\psi\rangle</math>: the quantum physical state <math>\psi</math>
* <math>\langle\psi|</math>: the [[dual space|dual state]] corresponding to the state above
* <math>\langle\psi|\rho\rangle</math>: the [[inner product]] of states <math>\psi</math> and <math>\rho</math>
* [[Supergroup (physics)|Supergroups in physics]] are denoted ''G''(''N''|''M''), which reads "''G'', ''M'' vertical bar ''N''"; here ''G'' denotes any supergroup, ''M'' denotes the [[bosonic dimensions]], and ''N'' denotes the [[Grassmann dimensions]].<ref>Larus Thorlacius, Thordur Jonsson (eds.), ''M-Theory and Quantum Geometry'', Springer, 2012, p. 263.</ref>